权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Temperature resistant electrochromic micro-iris with neutral color for quick image adaptation in micro-cameras for medical applications

具有中性颜色的耐温电致变色微虹膜，可在医疗应用的微型相机中快速调整图像

基本信息

批准号：
317515858
负责人：
Professor Dr. Egbert Oesterschulze
金额：
--
依托单位：
Organische Chemie - Molekulare Elektrochemie
依托单位国家：
德国
项目类别：
Research Grants (Transfer Project)
财政年份：
2016
资助国家：
德国
起止时间：
2015-12-31 至 2019-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/317515858?language=en
关键词：
Temperature resistant electrochromic micro iris

项目摘要

The project aims at the technical realization and scientific investigation of a multilevel non-mechanical electrochromic (EC) iris. We intend to integrate the tunable EC-iris inside a human endoscope with chip on the tip technology, which limits its diameter to 5 mm. The endoscope with integrated iris would enable surgeons for the first time to adapt the important optical features like the depth of focus or the image contrast on-the-fly. However, as part of a medical system, the EC-iris has to fulfill all demanding requirements of an endoscope. This includes the small space requirements, the temperature stability up to 140°C during sterilization, and a response time below 0.5 s. Furthermore, the desired application demands a high optical image quality. Thus, each segment of the iris should have an optical contrast of at least 90%, low optical scattering, and a neutral spectral absorption response. The strong reduction of the response time can only be achieved by chemical binding the EC-molecules to a solid and transparent electrode. In fact, the desired high contrast of the iris demands to increase the overall absorption by establishing conductive porous layers made of nanoparticles. Their surface is coated with the EC molecules enabling a much more effective charge transfer to the underlying electrode. The nanoparticle material choice needs to be adapted to the electrochemical reaction on the individual electrode. The synthesis of proper EC-molecules including the chemical anchor group is imperative not only for the appropriate electronic coupling to the nanoparticle. Choosing complementary EC molecules for the two electrodes gives the freedom to achieve an almost neutral spectral response in the opaque state. In addition to these chemically oriented tasks, several technological challenges have to be solved. The deposition of highly porous nano-electrodes of homogeneous thickness will be attained by doctor-blading of an emulsion followed by calcination and sintering. Prior to this process, the ITO layers as well as gold/chromium contact electrodes are assembled by well-established microstructuring techniques. The assembly of the EC cell is one of the main challenges which requires the parallel alignment and mounting of sub- and superstrate. However, in the same process we need to establish an air and moisture tight sealing of the electrolyte by an UV-epoxy to avoid degradation of the EC-molecules. Therefore, the entire assembly must be performed under nitrogen atmosphere. The reduction of both, reflection and scattering losses will be advanced by matching the refractive index of the electrolyte and the nanoparticles. The choice of materials is subject to restrictions because they need to withstand the temperature cycles during the sterilization process. Finally, each single iris needs to be separated by core drilling, electrically contacted in a very tight space, and ultimately integrated into an endoscope to provide finally a demonstrator.

该项目旨在对多级非机械电致变色虹膜进行技术实现和科学研究。我们打算将可调谐的EC-虹膜集成到人类内窥镜中，并使用芯片顶端技术，将其直径限制在5毫米。集成虹膜的内窥镜将首次使外科医生能够动态调整重要的光学特征，如焦深或图像对比度。然而，作为医疗系统的一部分，EC-IRIS必须满足内窥镜的所有苛刻要求。这包括空间要求小，灭菌过程中温度稳定性高达140C，响应时间低于0.5S。此外，期望的应用对光学图像质量提出了更高的要求。因此，虹膜的每一段都应该具有至少90%的光学对比度、低的光学散射和中性的光谱吸收响应。只有将EC-分子化学结合到固体透明电极上，才能显著缩短响应时间。事实上，理想的高对比度虹膜需要通过建立由纳米颗粒组成的导电多孔层来增加整体吸收。它们的表面涂有EC分子，能够更有效地将电荷转移到下面的电极上。纳米粒子材料的选择需要适应单个电极上的电化学反应。合成合适的EC-分子，包括化学锚基，不仅是为了与纳米粒子进行适当的电子耦合，而且是必不可少的。选择互补的EC分子作为两个电极，可以自由地在不透明状态下实现几乎中性的光谱响应。除了这些以化学为导向的任务外，还必须解决几个技术挑战。通过对乳状液进行刮刀处理，然后进行焙烧和烧结，可以获得厚度均匀的多孔性纳米电极。在此之前，ITO层以及金/铬接触电极是通过成熟的微结构技术组装的。EC电池的组装是一个主要的挑战之一，这就需要下层和上层的平行对准和安装。然而，在相同的过程中，我们需要用UV-环氧树脂对电解液进行空气和湿气的密封，以避免EC分子的降解。因此，整个装配必须在氮气气氛下进行。通过匹配电解液的折射率和纳米颗粒的折射率，可以促进反射和散射损耗的降低。材料的选择受到限制，因为它们需要承受灭菌过程中的温度循环。最后，每个单独的虹膜需要通过钻芯分离，在非常狭窄的空间内电接触，最终集成到内窥镜中，最终提供演示。